#pragma once


#define MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL               -0x002A  /**< Output buffer too small. */
#define MBEDTLS_ERR_BASE64_INVALID_CHARACTER              -0x002C  /**< Invalid character in input. */
#define BASE64_SIZE_T_MAX   ( (size_t) -1 ) /* SIZE_T_MAX is not standard */
typedef unsigned int       uint32_t;
inline static int mbedtls_base64_encode(unsigned char* dst, size_t dlen, size_t* olen, const unsigned char* src, size_t slen)
{
	static const unsigned char base64_enc_map[64] =
	{
		'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J',
		'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T',
		'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd',
		'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n',
		'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x',
		'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7',
		'8', '9', '+', '/'
	};

	size_t i, n;
	int C1, C2, C3;
	unsigned char* p;

	if (slen == 0)
	{
		*olen = 0;
		return(0);
	}

	n = slen / 3 + (slen % 3 != 0);

	if (n > (BASE64_SIZE_T_MAX - 1) / 4)
	{
		*olen = BASE64_SIZE_T_MAX;
		return(MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL);
	}

	n *= 4;

	if ((dlen < n + 1) || (NULL == dst))
	{
		*olen = n + 1;
		return(MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL);
	}

	n = (slen / 3) * 3;

	for (i = 0, p = dst; i < n; i += 3)
	{
		C1 = *src++;
		C2 = *src++;
		C3 = *src++;

		*p++ = base64_enc_map[(C1 >> 2) & 0x3F];
		*p++ = base64_enc_map[(((C1 & 3) << 4) + (C2 >> 4)) & 0x3F];
		*p++ = base64_enc_map[(((C2 & 15) << 2) + (C3 >> 6)) & 0x3F];
		*p++ = base64_enc_map[C3 & 0x3F];
	}

	if (i < slen)
	{
		C1 = *src++;
		C2 = ((i + 1) < slen) ? *src++ : 0;

		*p++ = base64_enc_map[(C1 >> 2) & 0x3F];
		*p++ = base64_enc_map[(((C1 & 3) << 4) + (C2 >> 4)) & 0x3F];

		if ((i + 1) < slen)
			*p++ = base64_enc_map[((C2 & 15) << 2) & 0x3F];
		else *p++ = '=';

		*p++ = '=';
	}

	*olen = p - dst;
	*p = 0;

	return(0);
}

inline static int mbedtls_base64_decode(unsigned char* dst, size_t dlen, size_t* olen, const unsigned char* src, size_t slen)
{
	static const unsigned char base64_dec_map[128] =
	{
		127, 127, 127, 127, 127, 127, 127, 127, 127, 127,
		127, 127, 127, 127, 127, 127, 127, 127, 127, 127,
		127, 127, 127, 127, 127, 127, 127, 127, 127, 127,
		127, 127, 127, 127, 127, 127, 127, 127, 127, 127,
		127, 127, 127,  62, 127, 127, 127,  63,  52,  53,
			54,  55,  56,  57,  58,  59,  60,  61, 127, 127,
		127,  64, 127, 127, 127,   0,   1,   2,   3,   4,
			5,   6,   7,   8,   9,  10,  11,  12,  13,  14,
			15,  16,  17,  18,  19,  20,  21,  22,  23,  24,
			25, 127, 127, 127, 127, 127, 127,  26,  27,  28,
			29,  30,  31,  32,  33,  34,  35,  36,  37,  38,
			39,  40,  41,  42,  43,  44,  45,  46,  47,  48,
			49,  50,  51, 127, 127, 127, 127, 127
	};

	size_t i, n;
	uint32_t j, x;
	unsigned char* p;

	/* First pass: check for validity and get output length */
	for (i = n = j = 0; i < slen; i++)
	{
		/* Skip spaces before checking for EOL */
		x = 0;
		while (i < slen && src[i] == ' ')
		{
			++i;
			++x;
		}

		/* Spaces at end of buffer are OK */
		if (i == slen)
			break;

		if ((slen - i) >= 2 &&
			src[i] == '\r' && src[i + 1] == '\n')
			continue;

		if (src[i] == '\n')
			continue;

		/* Space inside a line is an error */
		if (x != 0)
			return(MBEDTLS_ERR_BASE64_INVALID_CHARACTER);

		if (src[i] == '=' && ++j > 2)
			return(MBEDTLS_ERR_BASE64_INVALID_CHARACTER);

		if (src[i] > 127 || base64_dec_map[src[i]] == 127)
			return(MBEDTLS_ERR_BASE64_INVALID_CHARACTER);

		if (base64_dec_map[src[i]] < 64 && j != 0)
			return(MBEDTLS_ERR_BASE64_INVALID_CHARACTER);

		n++;
	}

	if (n == 0)
	{
		*olen = 0;
		return(0);
	}

	/* The following expression is to calculate the following formula without
		* risk of integer overflow in n:
		*     n = ( ( n * 6 ) + 7 ) >> 3;
		*/
	n = (6 * (n >> 3)) + ((6 * (n & 0x7) + 7) >> 3);
	n -= j;

	if (dst == NULL || dlen < n)
	{
		*olen = n;
		return(MBEDTLS_ERR_BASE64_BUFFER_TOO_SMALL);
	}

	for (j = 3, n = x = 0, p = dst; i > 0; i--, src++)
	{
		if (*src == '\r' || *src == '\n' || *src == ' ')
			continue;

		j -= (base64_dec_map[*src] == 64);
		x = (x << 6) | (base64_dec_map[*src] & 0x3F);

		if (++n == 4)
		{
			n = 0;
			if (j > 0) *p++ = (unsigned char)(x >> 16);
			if (j > 1) *p++ = (unsigned char)(x >> 8);
			if (j > 2) *p++ = (unsigned char)(x);
		}
	}

	*olen = p - dst;

	return(0);
}

